1. Field of the Invention
The present invention relates to an apparatus for selecting points for use in an on-board (mounted in a vehicle) navigation system.
2. Description of Background Information
Recently, navigation systems to be mounted in a vehicle have been developed and are entering into a stage of practical application. Navigation systems are constructed such that digitized map data is previously stored in a memory, map data of a region covering a given area including the present position of the vehicle is read out from the memory while the present position of the vehicle is being recognized, so that a map around the location of the vehicle is displayed on a display, and a "vehicle's own position" indicating the present position of the vehicle is automatically indicated in the map being displayed.
In the case of such navigation systems, a number of key operations are required for generating various commands. However, there inherently are spatial limitations since such navigation systems are to be installed in the vehicle. Moreover, in view of the fact that the keys are to be operated by the driver while driving the vehicle, the number of operation keys should be reduced to be as small as possible. On the other hand, the number of operation keys can be reduced by assigning a plurality of functions to each of the operation keys. However, it would be senseless if the key operation becomes intricate by assigning a plurality of functions to each operation key.